Grammar

To put the nuts and bolts together first, think about how it is formed. You need to be sure how to form...

The Imperfect Subjunctive or (Konjunktiv II)

This has 3 different ways of forming itself, depending on the type of verb.

Weak verbs : - exactly the same as the normal imperfect.

Strong verbs : - Strong stem + ¨ if a,o or u in stem plus these endings ......

e.g. sehen - SAH

ich sähE
du sähEST
er
sie sähE
es

wir sähEN
ihr sähET
sie sähEN

Mixed verbs : - stem + weak endings i.e. NO stem change.

e.g. rennen ich rennTE
etc

You should get used to

sein ich wäre
haben ich hätte
werden ich würde

The conditional is used for all that might happen, if something changes. It is often expressed with the imperfect subjunctive.

It is formed.........

imperfect subjunctive of werden (würde) etc + INFINITIVE, This is very common in spoken German, but in written German in the wennteil, we tend to use the Imperfect subjunctive (Konjunktiv II).

Ich würde dieses Buch kaufen, wenn ich genug Geld hätte.
Würdest du in die Kneipe gehen, wenn ich mitkäme ?

You can also use it one step further back in the past...

If you want to talk about wished for changes in the past, which are no longer possible, then we need the CONDITIONAL PERFECT.

Imperfect subjunctive of werden + past participle + infinitive auxiliary.
or
Auxiliary in imperfect subjunctive (wäre / hätte) + past participle.

Wir wären früher angekommen, wenn es nicht geregnet hätte.

Can you translate these into German ?

If I were rich, I would travel abroad frequently.

If I could, I would buy a new car.

If he went to her party, he would behave badly.

Would you come to the cinema with me, if I could get tickets for Titanic ?

If I had known, I would have stayed at home.

I would not have eaten the meat, if I had known about mad cow disease.

If I had worked harder when I was at school, I would have gone to Oxford.....

If they had read the book, they would have understood everything.